As Alison Goldfrapp glides on stage, thigh cut high, shoulder-pads angular, hair curled, husky voice primed, it’s easy to forget how long she, a lovechild of Dusty Springfield, Debbie Harry and David Bowie, has been in this game.

Goldfrapp has an ageless quality, both in her look and the quality of her music. Yet this one-off gig at the Royal Albert Hall marks the 15th year of her ongoing collaboration with multi-instrumental composer Will Gregory.

A 25-piece orchestra is lined up behind her, with a synth to her right, bass, lead, a violinist and drums positioned in an arc. She’s given a single pool of white light, isolating her from the band and a capacity seated audience at London’s grandest venue.

She starts with Jo, the opening tune from Goldfrapp’s latest album, ‘Tales of Us’. It’s a showcase for her remarkable voice; breathy, smoky and fragile, often quiet and in every way ethereal. But she reserves the ability to cut through the soundscape her band creates with a single, perfectly-pitched, soaring cry.

There’s something strange and erotic about a woman who has become an LGBT icon without ever disclosing that much of her private life. It lies perhaps in the way she performs her lyrics and as she sways and bobs to the music, you are in the presence of a person meant to sing in such a giant dome.

‘Tales of Us’ is a spacious, dramatically rich album; a sort of folk-inspired, feminine-charged James Bond soundtrack. With songs like Clay, Jo, Thea, Stranger, and Simone, it is an evolution, albeit not a total departure, from the sometimes predictable prog-pop of her early career.

It is, in this writer’s opinion, her strongest album to date. The section culminates with Goldfrapp inviting 54 women on stage - local London choir Lips - to perform an astonishing version of Voicething, the final song on ‘Head First’. It’s the first time it’s been performed live.

Goldfrapp is famous for her nerves - or perhaps for being a bit of an old-fashioned diva. She rarely grants interviews; if she does a radio show, she will say hardly anything before the music begins. On stage, she laughs - often nervously - at the audience’s applause. She promises, at one stage, to talk to the audience about the stories that linger behind her songs, but - apart from telling us Annabel is about a woman inside the body of a man - any backstory is quickly forgotten.

Small moments punctuate the gig that suggest everything isn’t quite going to plan on stage, with Goldfrapp at one stage gesturing pretty pointedly at her violinist. But no matter to this crowd. A cult performer, Goldfrapp is one capable of commanding a devoted and slavish following. Many of them are in attendance this evening, and an expectancy hangs in the air that she will knock out the old, best-known classics.

After the choir interlude, she announces a special guest and John Grant, of Pale Green Ghosts fame, strides on stage. Together they sing Seventh Tree’s Monster Love and then a florid cover of Nancy and Lee’s Some Velvet Morning. But given the vocal ammunition of both, the duets only hint at the power of each.

The hits begin to come from ‘Rocket’ and ‘Head First’, including Little Bird, Ooh La La, Lovely Head and Train. A section of the choir remains on stage, elevating the sound even further. Yet they feel under-utilised, while the orchestra, so adept at adding to the sonorous minimalism of the first act, starts competing for space with, and then flooding, the pumped-up synth lines and guitar licks of her earlier, more radio-friendly material. At moments, this up-tempo material is breathtaking, like the vocal flourishes she unleashes at the end of Utopia. At other times, it feels over-cooked, excessive.

But, as the crowd respond with glee at her request to stand and jive along to the closing song of Caravan Girl, it’s difficult to feel resentful, or to bemoan too much the lack of comparative nuance in this happy-clappy section. “This is the last gig we’ll be doing for some time,” she shares, and it’s difficult not to to feel privileged at witnessing it, not to mention hopeful that her sound will grow again, and before too long.